DE 10 2009 042 981 A1 discloses an intercooler of the generic type having an air-inlet tank and an air-outlet tank and having a condensate collector for collecting condensate separated off in the intercooler. Also provided is a condensate line, which is connected to the condensate collector via an entrance and to an air-intake manifold via an exit. This is intended to give rise to differential-pressure-induced extraction of condensate from the condensate collector during operation of the intercooler, as a result of which it is possible to dispense with in particular hitherto used actuators, flaps or valves and/or control means.
DE 10 2009 011 634 A1, in turn, discloses an intercooler of the generic type in which a condensate line extracts condensate from the condensate collector continuously, as a reaction to a gradient generated by a throttle valve, as long as an engine is in the switched-on state.
DE 10 2008 045 685 A1 discloses an internal-combustion-engine arrangement having an internal combustion engine, a charge-air compressor, a low-pressure exhaust-gas-recirculation means, an intercooler and a charge-air line. Provision is made here for the intercooler to have, at the lowermost point of its air channel, a closable condensate-discharge opening, which is connected to the charge-air line via a condensate-discharge line. This is intended to make it possible to control discharge of condensate into the charge-air line.
In general, it may be the case, depending on environmental conditions (temperature and relative air humidity) and the prevailing operating conditions, that condensate occurs in the intercooler: on the one hand preferably at low load and low charge pressure and, on the other hand, in the case of low-pressure exhaust-gas recirculation. This may result in the charge-air-cooling operation being adversely affected, in particular at an ambient temperature below freezing, at which point the condensate collected can freeze. The passage of the charge air through the intercooler is partially blocked as a result. Much more critical, however, is the volume expansion of the water as it freezes, which may result in burst pipes in the intercooler. It is also possible for the internal combustion engine to be subjected to in some cases irreparable damage if all the condensate collected in its entirety enters suddenly into the internal combustion engine.
For this reason, the prior art discloses the practice of avoiding condensate in the intercooler or of discharging condensate from the intercooler, for which purpose for example actuator-operated opening flaps or valves are provided. Bypass lines around the intercooler are also known. Additionally known from the prior art is the practice of extracting the condensate permanently, and without any additional actuators or flaps or valves being used, on account of a differential pressure between an air-intake manifold and a condensate collector on the intercooler.
The disadvantage with the solutions known from the prior art, however, is that either they are expensive and of complex design or they require a condensate line to be installed separately.